Hi,
Some of you might have picked up on my somewhat disjointed line of questions from the IRC, I'm putting this into an email so it's searchable better.

Quick background, I'm trying to find a way to boot both UEFI and Legacy disks; turns out it's not so straightforward for someone who doesn't code at all. I'm still a bit surprised there's no way to do this out-of-the-box since most machines these days support both via CSMs, right?

More specifically, I'm investigating using SeaBIOS + DUET; as this seems easier than modifying Tianocore to accept a CSM and seems to "almost" work if you squint at it.

I'm starting with trying to get DUET working off of a flash drive, for which I've tried all three flavors given here. All of them will boot my desired UEFI disk on an old Thinkpad X61 (C2D!) as well as my current work machine (Lenovo P50 - i7-6820HQ).

However, this USB will NOT boot the machine I actually want to use (X210 - i7-8650u). It gets as far as the memory test (supposedly successfully), but then I get a solid cursor forever, not even a shell.

On the X61, it "waits" here for several minutes as well and ultimately continues booting, but on the X210 it never continues.

So this tells me DUET as a concept does work, but I have no idea what is causing the freeze.

Does anyone have some suggestions what I might look for / how I might debug this / different versions to try?

Cheers,

Rafael